<template>
  <view class="u-upload" :style="[$u.addStyle(customStyle)]">
    <view class="u-upload__wrap">
      <template v-if="previewImage">
        <view
          class="u-upload__wrap__preview"
          v-for="(item, index) in lists"
          :key="index"
        >
          <image
            v-if="item.isImage || (item.type && item.type === 'image')"
            :src="item.thumb || item.url"
            :mode="imageMode"
            class="u-upload__wrap__preview__image"
            @tap="onPreviewImage(item)"
            :style="[
              {
                width: $u.addUnit(width),
                height: $u.addUnit(height),
              },
            ]"
          />
          <view v-else class="u-upload__wrap__preview__other">
            <u-icon
              color="#80CBF9"
              size="26"
              :name="
                item.isVideo || (item.type && item.type === 'video')
                  ? 'movie'
                  : 'folder'
              "
            ></u-icon>
            <text class="u-upload__wrap__preview__other__text">
              {{
                item.isVideo || (item.type && item.type === "video")
                  ? "视频"
                  : "文件"
              }}
            </text>
          </view>
          <view
            class="u-upload__status"
            v-if="item.status === 'uploading' || item.status === 'failed'"
          >
            <view class="u-upload__status__icon">
              <u-icon
                v-if="item.status === 'failed'"
                name="close-circle"
                color="#ffffff"
                size="25"
              />
              <u-loading-icon size="22" mode="circle" color="#ffffff" v-else />
            </view>
            <text v-if="item.message" class="u-upload__status__message">
              {{ item.message }}
            </text>
          </view>
          <view
            class="u-upload__deletable"
            v-if="item.status !== 'uploading' && (deletable || item.deletable)"
            @tap.stop="deleteItem(index)"
          >
            <view class="u-upload__deletable__icon">
              <u-icon name="close" color="#ffffff" size="10"></u-icon>
            </view>
          </view>
          <view class="u-upload__success" v-if="item.status === 'success'">
            <!-- #ifdef APP-NVUE -->
            <image :src="successIcon" class="u-upload__success__icon"></image>
            <!-- #endif -->
            <!-- #ifndef APP-NVUE -->
            <view class="u-upload__success__icon">
              <u-icon name="checkmark" color="#ffffff" size="12"></u-icon>
            </view>
            <!-- #endif -->
          </view>
        </view>
      </template>

      <template v-if="isInCount">
        <view v-if="$slots.default || $slots.$default" @tap="chooseFile">
          <slot />
        </view>
        <view
          v-else
          class="u-upload__button"
          :hover-class="!disabled ? 'u-upload__button--hover' : ''"
          hover-stay-time="150"
          @tap="chooseFile"
          :class="[disabled && 'u-upload__button--disabled']"
          :style="[
            {
              width: $u.addUnit(width),
              height: $u.addUnit(height),
            },
          ]"
        >
          <u-icon
            :name="uploadIcon"
            size="26"
            :color="uploadIconColor"
          ></u-icon>
          <text v-if="uploadText" class="u-upload__button__text">
            {{ uploadText }}
          </text>
        </view>
      </template>
    </view>
  </view>
</template>

<script>
  import { chooseFile } from "./utils";
  import mixin from "./mixin.js";
  import props from "./props.js";

  /**
   * upload 上传
   * @description 该组件用于上传图片场景
   * @tutorial https://uviewui.com/components/upload.html
   * @property {String}			accept				接受的文件类型, 可选值为all media image file video （默认 'image' ）
   * @property {String | Array}	capture				图片或视频拾取模式，当accept为image类型时设置capture可选额外camera可以直接调起摄像头（默认 ['album', 'camera'] ）
   * @property {Boolean}			compressed			当accept为video时生效，是否压缩视频，默认为true（默认 true ）
   * @property {String}			camera				当accept为video时生效，可选值为back或front（默认 'back' ）
   * @property {Number}			maxDuration			当accept为video时生效，拍摄视频最长拍摄时间，单位秒（默认 60 ）
   * @property {String}			uploadIcon			上传区域的图标，只能内置图标（默认 'camera-fill' ）
   * @property {String}			uploadIconColor		上传区域的图标的字体颜色，只能内置图标（默认 #D3D4D6 ）
   * @property {Boolean}			useBeforeRead		是否开启文件读取前事件（默认 false ）
   * @property {Boolean}			previewFullImage	是否显示组件自带的图片预览功能（默认 true ）
   * @property {String | Number}	maxCount			最大上传数量（默认 52 ）
   * @property {Boolean}			disabled			是否启用（默认 false ）
   * @property {String}			imageMode			预览上传的图片时的裁剪模式，和image组件mode属性一致（默认 'aspectFill' ）
   * @property {String}			name				标识符，可以在回调函数的第二项参数中获取
   * @property {Array}			sizeType			所选的图片的尺寸, 可选值为original compressed（默认 ['original', 'compressed'] ）
   * @property {Boolean}			multiple			是否开启图片多选，部分安卓机型不支持 （默认 false ）
   * @property {Boolean}			deletable			是否展示删除按钮（默认 true ）
   * @property {String | Number}	maxSize				文件大小限制，单位为byte （默认 Number.MAX_VALUE ）
   * @property {Array}			fileList			显示已上传的文件列表
   * @property {String}			uploadText			上传区域的提示文字
   * @property {String | Number}	width				内部预览图片区域和选择图片按钮的区域宽度（默认 80 ）
   * @property {String | Number}	height				内部预览图片区域和选择图片按钮的区域高度（默认 80 ）
   * @property {Object}			customStyle			组件的样式，对象形式
   * @event {Function} afterRead		读取后的处理函数
   * @event {Function} beforeRead		读取前的处理函数
   * @event {Function} oversize		文件超出大小限制
   * @event {Function} clickPreview	点击预览图片
   * @event {Function} delete 		删除图片
   * @example <u-upload :action="action" :fileList="fileList" ></u-upload>
   */
  export default {
    name: "u-upload",
    mixins: [uni.$u.mpMixin, uni.$u.mixin, mixin, props],
    data() {
      return {
        // #ifdef APP-NVUE
        successIcon:
          "",
        // #endif
        lists: [],
        isInCount: true,
      };
    },
    watch: {
      // 监听文件列表的变化，重新整理内部数据
      fileList: {
        immediate: true,
        handler() {
          this.formatFileList();
        },
      },
    },
    methods: {
      formatFileList() {
        const { fileList = [], maxCount } = this;
        console.log(this.accept);
        const lists = fileList.map((item) =>
          Object.assign(Object.assign({}, { url: item }), {
            // 如果item.url为本地选择的blob文件的话，无法判断其为video还是image，此处优先通过accept做判断处理
            isImage: this.accept === "image" || uni.$u.test.image(item),
            isVideo: this.accept === "video" || uni.$u.test.video(item),
            deletable:
              typeof item.deletable === "boolean"
                ? item.deletable
                : this.deletable,
          })
        );
        console.log(lists, fileList);
        this.lists = lists;
        this.isInCount = lists.length < maxCount;
      },
      chooseFile() {
        const { maxCount, multiple, lists, disabled } = this;
        if (disabled) return;
        // 如果用户传入的是字符串，需要格式化成数组
        let capture;
        try {
          capture = uni.$u.test.array(this.capture)
            ? this.capture
            : this.capture.split(",");
        } catch (e) {
          capture = [];
        }
        chooseFile(
          Object.assign(
            {
              accept: this.accept,
              multiple: this.multiple,
              capture: capture,
              compressed: this.compressed,
              maxDuration: this.maxDuration,
              sizeType: this.sizeType,
              camera: this.camera,
            },
            {
              maxCount: maxCount - lists.length,
            }
          )
        )
          .then((res) => {
            this.onBeforeRead(multiple ? res : res[0]);
          })
          .catch((error) => {
            this.$emit("error", error);
          });
      },
      // 文件读取之前
      onBeforeRead(file) {
        const { beforeRead, useBeforeRead } = this;
        let res = true;
        // beforeRead是否为一个方法
        if (uni.$u.test.func(beforeRead)) {
          // 如果用户定义了此方法，则去执行此方法，并传入读取的文件回调
          res = beforeRead(file, this.getDetail());
        }
        if (useBeforeRead) {
          res = new Promise((resolve, reject) => {
            this.$emit(
              "beforeRead",
              Object.assign(
                Object.assign(
                  {
                    file,
                  },
                  this.getDetail()
                ),
                {
                  callback: (ok) => {
                    ok ? resolve() : reject();
                  },
                }
              )
            );
          });
        }
        if (!res) {
          return;
        }
        if (uni.$u.test.promise(res)) {
          res.then((data) => this.onAfterRead(data || file));
        } else {
          this.onAfterRead(file);
        }
      },
      getDetail(index) {
        return {
          name: this.name,
          index: index == null ? this.fileList.length : index,
        };
      },
      onAfterRead(file) {
        const { maxSize, afterRead } = this;
        const oversize = Array.isArray(file)
          ? file.some((item) => item.size > maxSize)
          : file.size > maxSize;
        if (oversize) {
          this.$emit(
            "oversize",
            Object.assign(
              {
                file,
              },
              this.getDetail()
            )
          );
          return;
        }
        if (typeof afterRead === "function") {
          afterRead(file, this.getDetail());
        }
        this.$emit(
          "afterRead",
          Object.assign(
            {
              file,
            },
            this.getDetail()
          )
        );
      },
      deleteItem(index) {
        this.$emit(
          "delete",
          Object.assign(Object.assign({}, this.getDetail(index)), {
            file: this.fileList[index],
          })
        );
      },
      // 预览图片
      onPreviewImage(item) {
        if (!item.isImage || !this.previewFullImage) return;
        uni.previewImage({
          // 先filter找出为图片的item，再返回filter结果中的图片url
          urls: this.lists
            .filter(
              (item) =>
                this.accept === "image" ||
                uni.$u.test.image(item.url || item.thumb)
            )
            .map((item) => item.url || item.thumb),
          current: item.url || item.thumb,
          fail() {
            uni.$u.toast("预览图片失败");
          },
        });
      },
      onPreviewVideo(event) {
        if (!this.data.previewFullImage) return;
        const { index } = event.currentTarget.dataset;
        const { lists } = this.data;
        wx.previewMedia({
          sources: lists
            .filter((item) => isVideoFile(item))
            .map((item) =>
              Object.assign(Object.assign({}, item), {
                type: "video",
              })
            ),
          current: index,
          fail() {
            uni.$u.toast("预览视频失败");
          },
        });
      },
      onClickPreview(event) {
        const { index } = event.currentTarget.dataset;
        const item = this.data.lists[index];
        this.$emit(
          "clickPreview",
          Object.assign(Object.assign({}, item), this.getDetail(index))
        );
      },
    },
  };
</script>

<style lang="scss" scoped>
  @import "../../libs/css/components.scss";
  $u-upload-preview-border-radius: 2px !default;
  $u-upload-preview-margin: 0 8px 8px 0 !default;
  $u-upload-image-width: 80px !default;
  $u-upload-image-height: $u-upload-image-width;
  $u-upload-other-bgColor: rgb(242, 242, 242) !default;
  $u-upload-other-flex: 1 !default;
  $u-upload-text-font-size: 11px !default;
  $u-upload-text-color: $u-tips-color !default;
  $u-upload-text-margin-top: 2px !default;
  $u-upload-deletable-right: 0 !default;
  $u-upload-deletable-top: 0 !default;
  $u-upload-deletable-bgColor: rgb(55, 55, 55) !default;
  $u-upload-deletable-height: 14px !default;
  $u-upload-deletable-width: $u-upload-deletable-height;
  $u-upload-deletable-boder-bottom-left-radius: 100px !default;
  $u-upload-deletable-zIndex: 3 !default;
  $u-upload-success-bottom: 0 !default;
  $u-upload-success-right: 0 !default;
  $u-upload-success-border-style: solid !default;
  $u-upload-success-border-top-color: transparent !default;
  $u-upload-success-border-left-color: transparent !default;
  $u-upload-success-border-bottom-color: $u-success !default;
  $u-upload-success-border-right-color: $u-upload-success-border-bottom-color;
  $u-upload-success-border-width: 9px !default;
  $u-upload-icon-top: 0px !default;
  $u-upload-icon-right: 0px !default;
  $u-upload-icon-h5-top: 1px !default;
  $u-upload-icon-h5-right: 0 !default;
  $u-upload-icon-width: 16px !default;
  $u-upload-icon-height: $u-upload-icon-width;
  $u-upload-success-icon-bottom: -10px !default;
  $u-upload-success-icon-right: -10px !default;
  $u-upload-status-right: 0 !default;
  $u-upload-status-left: 0 !default;
  $u-upload-status-bottom: 0 !default;
  $u-upload-status-top: 0 !default;
  $u-upload-status-bgColor: rgba(0, 0, 0, 0.5) !default;
  $u-upload-status-icon-Zindex: 1 !default;
  $u-upload-message-font-size: 12px !default;
  $u-upload-message-color: #ffffff !default;
  $u-upload-message-margin-top: 5px !default;
  $u-upload-button-width: 80px !default;
  $u-upload-button-height: $u-upload-button-width;
  $u-upload-button-bgColor: rgb(244, 245, 247) !default;
  $u-upload-button-border-radius: 2px !default;
  $u-upload-botton-margin: 0 8px 8px 0 !default;
  $u-upload-text-font-size: 11px !default;
  $u-upload-text-color: $u-tips-color !default;
  $u-upload-text-margin-top: 2px !default;
  $u-upload-hover-bgColor: rgb(230, 231, 233) !default;
  $u-upload-disabled-opacity: 0.5 !default;

  .u-upload {
    @include flex(column);
    flex: 1;

    &__wrap {
      @include flex;
      flex-wrap: wrap;
      flex: 1;

      &__preview {
        border-radius: $u-upload-preview-border-radius;
        margin: $u-upload-preview-margin;
        position: relative;
        overflow: hidden;
        @include flex;

        &__image {
          width: $u-upload-image-width;
          height: $u-upload-image-height;
        }

        &__other {
          width: $u-upload-image-width;
          height: $u-upload-image-height;
          background-color: $u-upload-other-bgColor;
          flex: $u-upload-other-flex;
          @include flex(column);
          justify-content: center;
          align-items: center;

          &__text {
            font-size: $u-upload-text-font-size;
            color: $u-upload-text-color;
            margin-top: $u-upload-text-margin-top;
          }
        }
      }
    }

    &__deletable {
      position: absolute;
      top: $u-upload-deletable-top;
      right: $u-upload-deletable-right;
      background-color: $u-upload-deletable-bgColor;
      height: $u-upload-deletable-height;
      width: $u-upload-deletable-width;
      @include flex;
      border-bottom-left-radius: $u-upload-deletable-boder-bottom-left-radius;
      align-items: center;
      justify-content: center;
      z-index: $u-upload-deletable-zIndex;

      &__icon {
        position: absolute;
        transform: scale(0.7);
        top: $u-upload-icon-top;
        right: $u-upload-icon-right;
        /* #ifdef H5 */
        top: $u-upload-icon-h5-top;
        right: $u-upload-icon-h5-right;
        /* #endif */
      }
    }

    &__success {
      position: absolute;
      bottom: $u-upload-success-bottom;
      right: $u-upload-success-right;
      @include flex;
      // 由于weex(nvue)为阿里巴巴的KPI(部门业绩考核)的laji产物，不支持css绘制三角形
      // 所以在nvue下使用图片，非nvue下使用css实现
      /* #ifndef APP-NVUE */
      border-style: $u-upload-success-border-style;
      border-top-color: $u-upload-success-border-top-color;
      border-left-color: $u-upload-success-border-left-color;
      border-bottom-color: $u-upload-success-border-bottom-color;
      border-right-color: $u-upload-success-border-right-color;
      border-width: $u-upload-success-border-width;
      align-items: center;
      justify-content: center;
      /* #endif */

      &__icon {
        /* #ifndef APP-NVUE */
        position: absolute;
        transform: scale(0.7);
        bottom: $u-upload-success-icon-bottom;
        right: $u-upload-success-icon-right;
        /* #endif */
        /* #ifdef APP-NVUE */
        width: $u-upload-icon-width;
        height: $u-upload-icon-height;
        /* #endif */
      }
    }

    &__status {
      position: absolute;
      top: $u-upload-status-top;
      bottom: $u-upload-status-bottom;
      left: $u-upload-status-left;
      right: $u-upload-status-right;
      background-color: $u-upload-status-bgColor;
      @include flex(column);
      align-items: center;
      justify-content: center;

      &__icon {
        position: relative;
        z-index: $u-upload-status-icon-Zindex;
      }

      &__message {
        font-size: $u-upload-message-font-size;
        color: $u-upload-message-color;
        margin-top: $u-upload-message-margin-top;
      }
    }

    &__button {
      @include flex(column);
      align-items: center;
      justify-content: center;
      width: $u-upload-button-width;
      height: $u-upload-button-height;
      background-color: $u-upload-button-bgColor;
      border-radius: $u-upload-button-border-radius;
      margin: $u-upload-botton-margin;
      /* #ifndef APP-NVUE */
      box-sizing: border-box;
      /* #endif */

      &__text {
        font-size: $u-upload-text-font-size;
        color: $u-upload-text-color;
        margin-top: $u-upload-text-margin-top;
      }

      &--hover {
        background-color: $u-upload-hover-bgColor;
      }

      &--disabled {
        opacity: $u-upload-disabled-opacity;
      }
    }
  }
</style>
